K I figured it out, for anyone wanting to run a dedicated server and play on there own server to see how its running and it works, you need to go to your games folder in steam.
1.open up system tray in win xp/vista/win7, double left click on steam icon.
2.at top is menu, go to games, then you must navigate to tools or game list. In tools there is your brink dedicated server or in games, your brink game. You need to right click both,
3. Click on set launch options on next window
4. You must put in +set win_allowMultipleInstances 1 just like that.
5. There you go, now start both up.